Friday, January 31, 2014

A forthcoming paper in Function Ecology by McCann et al. (2014) rerports the cane toad, Rhinella marina has now reached areas much colder than most of its native range in tropical America.

In northeastern New South Wales, cane toads have been recorded up to 1100 m above sea level (asl). The authors monitored the toad over the summer 2012 -2013 and confirmed that ground temperatures were lower at three high-elevation (750 to 1010 m asl) sites than at two nearby lower (100 to 210 m asl) sites. During the day 18 vs 25°C; and at night, 17 to 18 °C vs 20 to 25°C respectively.

Critical thermal minima (CTmins) of field-collected toads (loss of the righting reflex) were lower for high-elevation than low-elevation toads (5.5 vs 7.5°C), but laboratory acclimation erased this difference. A toad's CTmin was not affected by site of collection, nor by one month's exposure to warm (24°C) or cool (12°C) conditions; instead, a toad's CTmin was determined by its thermal exposure over the previous 12 h. Locomotor ability was affected by test temperature, by elevation, and by acclimation. Toads from high elevations exhibited equal endurance at cold and warm test temperatures after month-long acclimation to cold conditions, whereas toads from low elevations performed better at high temperatures regardless of previous temperature treatments.

Cane toads at the southern edge of their expanding Australian range can function under cool conditions by adjusting their thermal tolerance within a few hours of encountering low temperatures.

The toads’ ability for rapid thermal acclimation suggests that current models underestimate the potential range of abiotic conditions accessible to this invasive species.

Previous studies of leatherback turtles have analyzed surface movement patterns using only surface covariates. Since turtles and other marine predators spend the vast majority of their time diving underwater, an analysis of movement patterns at depth should yield insight into what drives their movements.

Photo credit DivingSeaSafari

In a new paper Scihick and colleagues (2013) analyze the movement paths of 15 post-nesting adult female Pacific leatherback turtles, which were caught and tagged on three nesting beaches in Mexico. The temporal length of the tracks ranged from 32 to 436 days, and the spatial distance covered ranged from 1,532 km to 13,097 km. The tracks were studied using a movement model designed to yield inference on the parameters driving movement. Because the telemetry data included diving depths, the authors extended an earlier version of the model that examined surface only movements, and analyze movements in 3-dimensions.

They tested the effect of dynamic environmental covariates from a coupled biophysical oceanographic model on patch choice in diving leatherback turtles, and compared the effects of parameters measured at the surface and at depth. The covariates included distance to future patch, temperature, salinity, meridional current velocity (current in the north–south direction), zonal current velocity (current in the east–west direction), phytoplankton density, diatom density, micro-plankton density, and meso-zooplankton density.

They found significant correlation between movement and the parameters for oceanic covariates in eight of the tracks. Of particular note, for one turtle they observed a lack of correlation between movements and a modeled index of zooplankton at the surface, but a significant correlation between movements and zooplankton at depth. Two of the turtles express a preference for patches at depth with elevated diatoms, and two turtles prefer patches with higher mezozooplankton values at depth. In contrast, four turtles expressed a preference for elevated zooplankton patches at the surface, but not at depth.

The authors suggest that our understanding of a marine predator’s response to the environment may change significantly depending upon the analytical frame of reference, that is whether relationships are examined at the surface, at depth, or at different temporal resolutions. They also tested the effects of accounting for ocean currents on the movement patterns and found that for 13 of the 15 turtles, the parameter governing distance to the next patch decreased.

Ever wanted to have a pet snake? Well, that could get a little harder soon. It looks like the snakes on Capitol Hill are teaming up with animal rights activists to make it harder for people to keep certain types of snakes as pets.

A bipartisan group of lawmakers sent a letter to the U.S. Fish and Wildlife Service to urging the agency to list the reticulated python, the DeSchauensee’s anaconda, the green anaconda, the Beni anaconda and the boa constrictor as “injurious species” under the Lacey Act. Such a listing would mean these snakes could not be imported or transported within the U.S.

Animal rights activists at the Humane Society support this designation, sending an email around quoting the lawmakers’ saying that these five snakes “pose a risk to the safety of the American people and threaten some of our nation’s most treasured natural habitats. Since 1990, twelve people died from encounters with ‘pet’ constrictor snakes, including two toddlers who were strangled in their cribs.”
Lawmakers have voiced similar concerns, arguing that these snakes are invasive and can damage local ecosystems and put a burden on taxpayers because federal officials have spent $6 million since 2005 combating Burmese pythons and other constrictor snakes in Florida.

“Yet, these predators continue to consume endangered and threatened species, kill family pets in residential neighborhoods, and have decimated almost 99 percent of Everglades’ small and medium sized native mammals,” reads the letter from lawmakers led by Oregon Democratic Rep. Peter DeFazio and Florida Republican Rep. Mario Diaz-Balart.

Lawmakers also cite a U.S. Geological Survey report saying that nine species of exotic constrictor snakes present a “high” or “medium” risk of becoming invasive species because of how easily they can escape from cages or because of owners releasing their pets into the wild. Four out of nine of these constrictors were listed as “injurious” under federal law, and now lawmakers want the other five to also be listed.

Reptile enthusiasts and owners, on the other hand, say this is a case of federal overreach and that local snake problems should be handled by the states, not the feds. A listing under the Lacey would not only ban importing and interstate trade of the snakes, but also intrastate trade where there is no existing state law on the matter — crippling the thousands of small, family-owned reptile businesses across the country.

“We believe that the listing of these constrictor snakes, which have been in the country for decades and are widely held as pets, is a one size fits all approach to a problem that at best is limited to the very southern tip of Florida,” Joan Galvin, a spokeswoman for the U.S. Association of Reptile Keepers, told The Daily Caller News Foundation.

Galvin added that most of the constrictor snakes being held as pets are bred to be certain colors and patterns, called “morphs”, meaning they would not even be able to blend into their ecosystems when released. This is on top of the snake’s inability to survive in climates that can drop into the 40s.

“The state of Florida, to their credit, has already addressed the issue at the state level at the initiative of their state wildlife management agency,” Galvin said. “We believe that is appropriate and that the use of the Lacey Act to prohibit the ownership of animals widely held as pets throughout the country is federal overreach, not supported by the science and would cause significant economic harm to those in the industry.”

The Center for North American Herpetology (CNAH) has announce the launch of their new journal – The Journal of North American Herpetology. The Journal of North American Herpetology (JNAH) (ISSN 2333-0694) provides an open access on-line venue with the use of all modern digital technologies for peer-reviewed contributions of all aspects of North American Herpetology within the geographic boundaries of the United States and Canada. JNAH is a continuation of the very first herpetological on-line peer reviewed journal Contemporary Herpetology (1998-2009), which can be accessed from the JNAH web site.

Co-editors and CNAH Board Members Walter Meshaka and Dan Fogell along with Managing Editor and CNAH Director Travis Taggart worked diligently over the past year preparing this new journal. JNAH will continue to publish manuscripts in this volume throughout 2014 as they are received, reviewed, and readied for publication. Subsequent announcements will be released each time an article is prepared for publication.

The premiere issue, Volume 2014(1), can be accessed by visiting the JNAH web site at http://jnah.cnah.org and includes the following authors and titles:

J. Whitfield Gibbons and Michael Dorcas – What is a herpetologist and how can I become one?
Jason T. Cotter and Chris A. Sheil – Hatchling sex ratios and locomotor performance of Midland Painted Turtles (Chrysemys picta marginata).

Malcolm L. McCallum and Jamie L. McCallum – Ecological release of an exotic species upon suppression of its invasive predator: A five-year case study, with notes on other species, and the life history of the Mediterranean Gecko, Hemidactylus turcicus.

Brian S. Gray – Natural history of Dekay’s Brown Snake, Storeria dekayi (Holbrook, 1836), at a site in northwestern Pennsylvania.

Monday, January 27, 2014

As the male túngara frog serenades female frogs from a pond, he creates watery ripples that make him easier to target by rivals and predators such as bats, according to researchers from The University of Texas at Austin, the Smithsonian Tropical Research Institute (STRI), Leiden University and Salisbury University.

A túngara frog will stop calling if it sees a bat overhead, but ripples continue moving for several seconds after the call ceases. In the study, published this week in the journal Science, researchers found evidence that bats use echolocation -- a natural form of sonar -- to detect these ripples and home in on a frog. The discovery sheds light on an ongoing evolutionary arms race between frogs and bats.

The male túngara frog (Physalaemus pustulosus), native to Central and South America, spends his nights calling from shallow ponds, attempting to attract the attention of a mate. Yet his call, which is based on a pattern of "whines" and "chucks," inadvertently creates a multisensory display that can be exploited by both friend and foe.

As the amorous amphibian calls out, his vocal sac continually inflates and deflates, like a pulsing balloon. This pulsating sac creates a visual cue, but also creates a third signal -- ripples in the surface of the pond.

"A general theme of this research is that the way we communicate with any kind of a signal is by creating a disturbance in the environment," said Mike Ryan, co-author on the study and professor in the Department of Integrative Biology at UT Austin. "When we vocalize, we're causing changes in the air pressure around us and that's what our ears hear. When we use visual signals, light bounces off whatever pigments we're using and is transmitted to the receiver. Anything we do disturbs the environment, whether it's intended as a communication signal or not."

The researchers found that frog-eating bats (Trachops cirrhosus) were much more likely to attack a target that had both frog calls and ripples radiating from it than one with frog calls and no ripples. This suggests that they can detect these ripples, most likely with echolocation. However, bats appear to lose this advantage if the area around the frog is cluttered with leaf litter, which may stop the ripples from propagating.

"The interesting thing is that these frogs have evolved a strategy to escape predation," said lead author Wouter Halfwerk, a postdoctoral researcher at UT Austin who is also affiliated with STRI and Leiden University. "When a frog detects the shadow of a bat overhead, his first defense is to stop calling immediately. Unfortunately for the frog, the water ripples created by his call do not also stop immediately. The ripples continue to emanate out for several seconds, creating a watery bull's-eye on the frog. Bats use the ripples, thereby beating the anti-predator strategy."

On the other hand, the ripples seem to enhance the response of rival male frogs to the initial caller.
The researchers found that when a call was accompanied by ripples, other male frogs were more likely to respond than if the call was broadcast by itself. In addition, when they did respond, they did so with more gusto.

If a call accompanied by water ripples was outside a male's zone of defense, a circle about 15 cm across, rival males would call more than twice as fast as they would if they just heard the initial call by itself. If the call, again with ripples, was inside their territory rival frogs tended to call less, often stopping altogether and deflating their vocal sacs, presumably getting ready to rumble or run.

The Schouteden’s sun snake Helophis schoutedeni is the sole member of the genus, and was originally described by the Belgian herpetologist Gaston-François de Witte in 1922 as Pelophis schoutedeni. Twenty years later, the new generic name Helophis was established by de Witte and Laurent because the generic name Pelophis was preoccupied by Pelophis Fitzinger, 1843. De Witte and later de Witte & Laurent (1942) provided data on two syntypes both collected by Henri Schouteden in 1921. In the original description, De Witte & Laurent also reported a third specimen from Léopoldville (today Kinshasa), which was collected in 1937 by Henrard. Since then, this snake species was all but forgotten, left out of field guides and faunal lists. And, the genus has remained monotypic.

In a recent article Nagy and colleagues (2014) report on a fourth specimen of this snake collected during a field expedition to the Democratic Republic of the Congo in June–July 2012. The authors obtained the snake in Kinshasa, in proximity of the Congo River.

Ecologically, Helophis schoutedeni is a semi-aquatic snake as suggested by its dorsally-oriented nostrils, narrow triangular internasals, small eyes with round pupil and stout body. And, during a short period in captivity, the snake preferred to stay in water. Helophis is morphologically similarity to the genus Hydraethiops another poorly known aquatic snake from Africa.

The photos here are most like the first ones take of live specimen of this species.

Burrowing snakes remain the most difficult serpents to study and undoubtedly represent a disproportionately large percentage of undescribed taxa. Burrowing species are found in many different clades, and a few clades contain only burrowing species. The shieldtail snakes of the family Uropeltidae are dedicated burrowers inhabiting southern India and Sri Lanka. The family contains about 60 species in eight genera, all are small to medium-sized, use wet hill forest and are viviparous. Most seem to feed on earthworms.

The genus Uropeltis has 26 valid species and is thought to have a confused taxonomy in need of revision. In a new paper Ganesh and colleagues (2014) elevate Uropeltis arcticeps madurensis to species level, and revive Silybura shortti (in the combination Uropeltis shorttii) from the synonymy of Uropeltis ceylanicus.Uropeltis shorttii is restricted to the Shevaroy Hills, part of southern Eastern Ghats located in Tamil Nadu. Today the area is heavily cultivated with coffee and silver oak but has remnant patches of tropical evergreen cloud forests that harbor wet-forest taxa such as the endemic Yercaud Day Gecko Cnemaspis yercaudensis. A live specimen was encountered in an area of silver oak, coffee plantations and small patches of evergreen forests in Yercaud (1550m) at the summit of Shevaroys. The only other Uropeltis occurring with U. shorttii is U. ellioti, an apparently widespread species belonging to a different species group.

Uropeltis madurensis is endemic to HighWavys-Varushanad-Periyar hill complex and it was studied in a cloud forest-plantation matrix in High Wavys between December 2007 and January 2008, in the post-monsoon season. Four adults were observed on a plateau at about 1300–1600 m. The snakes were observed under a rock streamside in a rainforest tract; actively moving about on forest floor on a rainy day; road-killed in coffee plantation; and under a small cement slab near a building.

The authors imply that cryptic diversity within the Uropeltis ceylanic Group is greater than current systematics would suggest.

Sunday, January 26, 2014

Alessandro Catenazzi, Edgar Lehr, and Rudolf von May (2014) have compile a list of all amphibians and reptiles known to occur within Manú National Park, Peru as well as its buffer zone. The park is located in one of the world’s biodiversity hotspots. Covering approximately 0.01% of the planet’s terrestrial surface, this protected area holds 155 species of amphibians and 132 species of reptiles, corresponding to 2.2% and 1.5% respectively of the known diversity for these groups. Manú National Park also preserves natural habitats and populations of the critically endangered (Atelopus erythropus), three endangered (Bryophrynecophites, Pristimantis cosnipatae and Psychrophrynella usurpator), three vulnerable amphibians (Atelopus tricolor, Gastrotheca excubitor, Rhinella manu); and two vulnerable reptiles (Chelonoidis denticulata, Podocnemis unifilis), according to the threat categories of the IUCN Red List.

Unfortunately the authors report, the montane amphibian fauna within the park and the adjacent Kosñipata valley have recently experienced dramatic declines and local extinctions. The collapse of amphibian diversity and abundance has been more pronounced at mid-elevations (1200-2000 m) and for stream-breeding species. These declines occurred over less than a decade and coincided with the arrival of the pathogenic fungus Batrachochytrium dendrobatidis (Bd) to southern Peru. The sudden disappearance of a sizable proportion of the montane anuran fauna despite the excellent state of conservation of the forest and protection granted by Manú NP shows that additional conservation actions are needed to preserve amphibian biodiversity.

Squamates and anurans constitute the bulk of reptile and amphibian diversity. Given the wide elevational gradient and large area of montane and high-elevation habitats protected by Manú National Park, the greater relative richness of anurans vs. squamates is probably replicated across several watersheds (and not just the Kosñipata watershed), adds to the species richness.

In an interview with National Geographic, von May said, "Manú now stands as the park or protected area with the highest number of species of amphibians and reptiles on the planet." Follow the link to see more photos of the herpetofauna of Manú.

Prior to this study, Yasuní National Park in Ecuador was first, with 150 amphibian and 121 reptile species. Both Manú and Yasuní protect large areas of lowland rain forest, but Manú also spans high-elevation cloud forests and Andean grasslands.

Friday, January 24, 2014

By David Mildenberg January 23, 2014
In a West Texas prairie of cactus and mesquite, Riley Sawyers sprays gasoline fumes into a narrow crevice in the ground, hoping to drive slumbering rattlesnakes to the surface. His equipment isn’t fancy, just a common pesticide canister attached to a long, thin copper tube. The smell of gasoline fills the air, but no snakes emerge on a 45-degree January day, disappointing Sawyers, a ponytailed tile mason who rounds up snakes on the side. Sawyers says that on a good day he’s captured as many as 56, grabbing them with 4-foot tongs as they emerge for air. It’s a sport revered in rural Texas—especially in Sweetwater, 200 miles west of Dallas, where every March thousands of snakes that hunters capture in the first three months of the year are brought to the Rattlesnake Round-Up to be slaughtered and sold for meat, leather, and venom vaccines. Sawyers’s snake-wrangling skills have made him something of a celebrity in Sweetwater and got him a recurring part on the Animal Planet reality show Rattlesnake Republic, where teams of Texans compete to round up the vipers.

Photograph by Albert Cesare/Odessa American/AP Photo

The hunt may soon become a lot more challenging. Texas environmental officials want to join 29 states that have already banned the use of noxious substances to collect or harass nongame wildlife, citing evidence that gassing, as it’s called, endangers at least 26 animals and insect species sharing underground caverns with snakes. “The research shows quite a compelling case for biological concern,” says John Davis, director of Texas’s wildlife diversity program. “We’re trying to do everything we can to keep species healthy.”

Standing up for endangered species is unusual in Texas, where politicians have campaigned to stop federal efforts to protect the sand dune lizard, the lesser prairie chicken, and other animals whose habitats got in the way of oil and gas drilling. When he ran for the Republican presidential nomination in 2012, Governor Rick Perry recommended reforming the Endangered Species Act to help boost U.S. energy production. It’s not clear whether the proposed gassing ban has his support. The governor expects environmental officials “to take all facts into consideration before making their decision” on whether to ban the practice in March, says Perry spokeswoman Lucy Nashed.

“There’s no studies in this part of the country showing that we are damaging anything,” says Dennis Cumbie, a U.S. Department of Agriculture employee in Sweetwater who has organized opposition to the state’s plan. “The tree huggers or environmentalists—whatever you call them—think we’re hurting stuff. They are out to get us.” Davis counters that decades of research in Texas and states around the country have firmly established the toxic effects of gas vapors on snakes and other species.

More than 150 people packed into a Jan. 17 public forum in Sweetwater, where for two and a half hours citizens and representatives of the local Chamber of Commerce angrily made the case against the proposal. In Sweetwater, captured snakes provide cash and peace of mind. Hunters brought more than 1,000 vipers weighing up to 5 pounds to last year’s Rattlesnake Round-Up, where the festival’s sponsor, the Junior Chamber of Commerce, bought 2,160 pounds of live snakes at $13 a pound. Some snakes were kept alive and sold to dealers. Most were killed—a pneumatic hammer blow between the eyes, then the head chopped off—and eaten by festival-goers, who consumed about 1,000 pounds of fried rattler. “Everyone is excited when the roundup comes around, because it helps solve our problems,” says Jim Wilks, a Sweetwater lawyer and rancher who, like many others in the area, has lost cattle to snakebites. Each year a friend captures as many as 20 rattlesnakes on Wilks’s ranch to sell at the festival, he says.

A gassing ban would cut the number of rattlesnakes captured by as much as 80 percent, leading to a population explosion, says Sawyers, who plans to hunt for snakes almost every day in the weeks before the festival. “It’s not a rare occasion for people in West Texas to come across a rattlesnake in their backyard or crossing a street,” says Sweetwater Mayor Greg Wortham, who opposes a ban. “When someone’s 8-year-old daughter walks across the patio and has to step over a rattlesnake, that’s pretty serious.”

Thursday, January 23, 2014

A press release from the CBD.
ATLANTA— As the town of Whigham, Ga., prepares to host its annual “rattlesnake roundup” this weekend, the Center for Biological Diversity and its allies presented a petition with more than 50,000 signatures to the Whigham Community Club today asking that the state’s last roundup transition to a wildlife-friendly festival where no snakes are killed. The petition marks the second year in a row that tens of thousands of people have asked organizers to end the cruel and lethal contest, in which hunters compete for prizes by capturing rare eastern diamondback rattlesnakes. The snakes are displayed and then sold for their meat and skins.

All the state’s other roundups have abandoned the outdated practice of removing rare rattlers from the wild. Two years ago Claxton, Ga., replaced its roundup with the Claxton Rattlesnake and Wildlife Festival, featuring displays of captive rattlesnakes, along with many other educational wildlife exhibits. The new wildlife festival in Claxton received a boost in attendance and high praise from environmental groups, the Georgia Department of Natural Resources, biologists and others who have lobbied for years to end rattlesnake roundups.

“People are fascinated by the rare rattlers, and so am I,” said Collette Adkins Giese, a biologist and attorney at the Center who works to protect rare reptiles and amphibians. “I understand that folks attending the Whigham event want to see snakes, but it’s time to end this cruel hunting contest. Whigham could display captive snakes instead of getting hunters to catch imperiled wild snakes and sell them for slaughter.”

Lethal roundups are still held in at least four states: Georgia, Texas, Oklahoma and Alabama.

Once-common rattlesnakes are being pushed toward extinction not only by hunting pressure but also by habitat loss and road mortality. Analysis of data from four roundups in the southeastern United States shows a steady decline in the weights of prizewinning eastern diamondbacks and the number collected.

In 2011 the Center — along with allies and Dr. Bruce Means, an expert on the eastern diamondback rattlesnake — filed a petition to protect eastern diamondbacks under the Endangered Species Act. Last year the U.S. Fish and Wildlife Service found that the imperiled rattlers may deserve a place on the list of protected species and initiated a full status review.

“Thousands of people have asked the organizers of the Whigham roundup to stop killing snakes, but so far they’ve ignored us,” said Olivia Ries, the elementary-school-aged co founder of a Georgia-based environmental group called One More Generation. “They refuse to even meet with us to discuss how the Whigham event could go forward without harming animals.”

Background
The eastern diamondback is the largest rattlesnake in the world. Adults are typically 4 to 5 feet long and weigh 4 to 5 pounds, but a big snake can reach 6 feet in length and weigh 12 pounds or more. Scientific studies over the past decade have documented range-wide population declines and significant range contractions for the eastern diamondback.

People fear rattlesnakes, but in reality eastern diamondbacks pose a very small public-safety risk. The snakes are certainly venomous, but more people are killed every year by lightning strikes and bee stings. In fact the majority of snake bites occur when humans try to handle or kill snakes — so rattlesnake roundups actually endanger public health by encouraging the public to do just that. Still, malicious killings by those who perceive the snakes as a threat are contributing to the animals’ decline.

Woodland salamanders are small, lungless amphibians that live in moist, forest habitats throughout the U.S. and the world. Salamanders often serve as vital links in forest food chains; their population size and recovery from major disturbances can help predict the health of forest ecosystems. Now, researchers at the University of Missouri have determined that salamander population size reflects forest habitat quality and can predict how ecosystems recover from forest logging activity. MU researchers believe these findings can be translated to other species within forest ecosystems throughout the world.

"One of our primary interests is in conservation of amphibians and the habitats that they utilize," said Ray Semlitsch, Curators' Professor of biological sciences in the College of Arts and Science at MU. "We are trying to understand how land use, and particularly forest management, affects the survival of amphibians on the landscape. We also determined that salamander recovery -- or the amount of time it takes for salamanders to repopulate a cut forest area -- can help forest managers determine appropriate logging schedules."

Semlitsch and fellow researcher, Grant Connette, a graduate student in the Division of Biological Sciences, chose to study a forest area in the southern Appalachian Mountains that has the highest diversity of salamanders in the world. Although seldom seen in the daytime, these animals breathe using their wet skin and forage at night. The researchers conducted surveys of terrestrial salamanders, which don't rely on water or streams, to examine patterns of their abundance relative to timber harvest and species movement behavior. They discovered that forests logged more than 100 years ago may still be affecting salamanders today.

"Most conservation biologists study the pattern of change within a species -- for example, how they decline or how they recolonize after a major event," Semlitsch said. "Our lab takes it a step further by seeking to understand the causes of species decline. We're finding that population fluctuations depend on the animal's behavior, like their ability to disperse, following a major event like logging a forest and can last for many years."

Roughly half of all forest area in the United States is on public land, where modern forest management increasingly uses alternatives to clear-cutting. These techniques include limiting the size of logged areas and maintaining large areas of forest at highly mature stages, which may prove less disruptive to wildlife than clear-cutting. Semlitsch hopes to help find the balance between the economics of using natural resources and conservation and hopes to share this information with forest managers so they can make informed decisions about conservation and biodiversity.

Their research, "Life history as a predictor of salamander recovery rate from timber harvest in southern Appalachian forests, U.S.A." was published in Conservation Biology.

Wednesday, January 22, 2014

The lizard families Gerrhosauridae and Cordylidae form the clade Cordyliformes. But, there is a long history of disagreement as to whether this clade comprises a single family, Cordylidae or two families: Cordylidae and Gerrhosauridae, or one family with two subfamilies (Cordylinae and Gerrhosaurinae).

In a recently published study in Zootaxa, Bates et al. (2013) constructed a molecular phylogeny of the African plated lizard family Gerrhosauridae using two mitochondrial markers (ND2, 732 bp; 16S, 576 bp) and one nuclear marker (PRLR, 538 bp). The study showed that the subfamily Gerrhosaurinae consists of five major clades which the authors interpret as representing five genera. The genera Tetradactylus and Cordylosaurus were each recovered as monophyletic, but Gerrhosaurus as currently conceived is paraphyletic, consisting of three distinct genus-level assemblages. The two clades consisting of Gerrhosaurus major Duméril, 1851 and Gerrhosaurus validus Smith, 1849 are both described as new genera: Broadleysaurus and Matobosaurus. Two subspecies of ‘Gerrhosaurus major’ were historically separated on the basis of differences in color pattern but were found not to be reciprocally monophyletic, so the authors placed Gerrhosaurus bottegoi Del Prato, 1895 in the synonymy of Broadleysaurus major (Duméril, 1851) is rendered monotypic. Gerrhosaurus validus maltzahni De Grys, 1938 is genetically and morphologically well differentiated from G. v. validus and the two taxa also occur in allopatry. The authors therefore re-instate the former as Matobosaurus maltzahni (De Grys, 1938), resulting in Matobosaurus validus (Smith, 1849) being monotypic species. The authors also showed Gerrhosaurus comprises two major subclades, one consisting of Gerrhosaurus typicus + Gerrhosaurus skoogi and the other containing the remaining species. In this latter subclade the west-Central African.

Gerrhosaurus nigrolineatus is most closely related to Gerrhosaurus auritus rather than to G. nigrolineatus from East and Southern Africa. The west-Central African clade of G. nigrolineatus differs from the East and Southern African clade by a p-distance of 13.0% (ND2) and 6.9% (16S), and can be differentiated morphologically. The authors accordingly apply the name Gerrhosaurus intermedius Lönnberg, 1907 comb. nov. to populations from Kenya, Uganda, Rwanda, Tanzania, Malawi, Mozambique, Zimbabwe and South Africa previously identified under the name G. nigrolineatus. Their results also confirms Gerrhosaurus bulsi Laurent, 1954 is a distinct species and the sister taxon to a clade containing G. nigrolineatus, G. auritus and G. intermedius. The last four taxa form a closely-related ‘G. nigrolineatus species complex’ with a widespread distribution in Africa. Most closely related to this complex of species is Gerrhosaurus flavigularis Wiegmann, 1828 which has an extensive range in East and Southern Africa, and displays genetic substructure which requires further investigation. The status of Gerrhosaurus multilineatus Bocage, 1866, and Angolan populations referred to G. nigrolineatus, remains problematic.

The Peninsula Clarion is the daily newspaper of Alaska's Kenai Peninsula.

By DAN BALMERPeninsula Clarion
While feeding his dogs last Saturday, George Pierce of Kasilof noticed something out of place in his back yard — a garter snake.

The frozen reptile, 1 1/2 feet in length, was coiled up uncovered by the melting snow. Pierce, who has lived in Alaska for more than 25 years, said he would never expect to find a snake this far north.

“It’s an odd thing to find here especially this time of year,” he said. “Like it fell out of the sky. Not something you see everyday.”

As for the cause of death of the snake, while the above average temperatures this month might have been warm enough for the snake to survive outside, Pierce said the nick on the end of its tail suggests he may have run it over with his snow blower.

He said he could only speculate to how the slithering reptile retired in his yard.

Pierce said he lives a block away from Tustemena Elementary School on the Sterling Highway. Perhaps it is an escapee from a classroom show and tell or maybe the snake arrived here through transport from the Lower 48, he said.

Alaska Fish and Game wildlife biologist Jeff Selinger said snakes in Southcentral Alaska are not as far-fetched as one would think. The common garter snake is the only species of snake found in Alaska and can be found as far up as Northern Canada, he said.

Selinger said no snakes have been recorded living in the wild in the Kenai Peninsula, but that does not mean people cannot have them as an indoor pet. Some pet stores sell garter snakes, he said.

Another possibility that the snake arrived in Alaska via cargo ship, he said.

“(Garter snakes) live off insects and frogs,” he said. “It is not out of the question one could survive here, but our harsh climate makes it difficult in the winter.”

After 21 years, Our Best Friends pet store on Kalifornsky Beach Road went out of business last March. Selinger said the store did sell reptile pets. The Petco in Soldotna, which opened October 2012, is the only pet store in the central peninsula.

Petco employee Brittney Bickle said the Soldotna store does not have any garter snakes in stock, but said she is aware of one customer who keeps one as a pet and feeds them fish. Bickle recommends anyone interested in adopting a garter snake to inquire in the summertime.

Pierce may not know where the snake came from, but has learned to never rule anything out when living in Alaska.

By Jerry Roberts
AVALON, CATALINA ISLAND - Researchers could announce as early as this winter that the Catalina Island version of the Southern Pacific rattlesnake has enough differences from the mainland version of the serpent to declare it a separate subspecies.

"We're on the verge of perhaps doing that, but just can't at this point," says William K. Hayes, Ph.D., of the Department of Earth and Biological Sciences at Loma Linda University. "We're waiting for Carl Person to finish his dissertation, and he's still doing DNA testing."

Hayes and Person presented their findings so far under the title "Santa Catalina's Overlooked Rattlesnake: Ecology, Venom Composition, Historical Origin, and Unanswered Questions" at the Catalina Island Conservancy symposium last year.

Hayes, Person and colleagues Eric C. K. Gren and Wayne Kelln have noticed that the Catalina rattlesnake is distinguished from the mainland version of Southern Pacific rattler by its tendency to strike without warning. Most rattlers do rattle when disturbed, virtually warning potential victims of a pending assault by fangs. The Catalina version goes right for the chomp.

"Catalina individuals are also less likely to rattle when threatened, but are more inclined to bite when defending themselves," the Loma Linda report states.

The Catalina population lacks neurotoxicity, according to the report, which occurs among some but not all mainland populations. Neurotoxicity is damage to the brain and nervous system from toxic chemicals, which are present in some snake poisons.

The analysis also suggests that the Catalina rattlesnakes came to the Island by chance, across a huge barrier of water probably riding debris. They began from a very small founding population, probably resulting from a 'sweepstakes' dispersal over water, since Catalina has never been connected to the mainland, the scientists say. Unlike the other Channel Islands, which broke from the California coast over many millennia, Catalina rose from the ocean floor.

Further analysis suggests that this isolated Island rattler population represents a relict or surviving population of the "original" Southern Pacific rattlesnake, known to science as Crotalus oreganus helleri. Catalina's rattlesnake possibly arrived, according to the report, during the Pliocene Epoch or between 5.3 and 2.5 million years ago.

"Catalina specimens exhibit some morphological differences from the mainland population in blotch pattern and scalation," the report states. The blotches refer to the brownish-black dark markings down the snake's back, separated by lighter-colored bordering. Scalation refers to the arrangement - size, direction, number - of scales on a reptile (or fish). Hayes said that the Catalina snake differs so much physically from the mainland version that these morphological differences on their own are almost enough to declare the Island version a separate subspecies.

Hayes and Person said that many questions remain to be answered about the Catalina population, including:
Without congeneric competitors, does the Island population experience ecological release, occupying more habitats and taking a broader range of prey than the mainland population?
Do temperature differences from the mainland result in different periods of activity that influence frequency of encounters with humans? "Does the maritime environment, which is usually cooler and foggier, influence the snake in significant ways?" Hays said.

Can variation in the venom be linked to preferred prey or prey diversity?
Hays suggested that the "common garden experiment" would be of value - feed the Catalina snakes the same as the mainland Southern Pacific individuals and see what similarities and differences result.
"Our highest priority, however," Hays said, "will be to use this population to study incipient speciation. We can sequence various parts of the nuclear genome, with emphasis on SINEs, LINEs, and methylation patterns, and compare these with their mainland counterparts."

In genetic research, SINES refers to Short Interspersed Nuclear Element Sequence and LINES are Long Interspersed Nuclear Element Sequences. Both sequences in DNA research help delineate species differences and instances of sameness.

The Southern Pacific rattler, like all rattlesnakes, is in the family of pit vipers or Crotalinae. It is Catalina's only venomous snake.

The transition from water to land is one of the most fascinating enigmas of evolution. Especially since both fish terrestrial animals have groups of architects genes, Hoxa and Hoxd , necessary for the formation of fins, as well as that of members during embryonic development. Editor Denis Duboule, a professor at the University of Geneva and EPFL, a team of scientists studied the parallel structure and behavior of these genes in the mouse embryo and in the zebrafish. In both species, the researchers found a similar three-dimensional organization of DNA genes architects observed. They have concluded that the main mechanism used to shape members of tetrapods was already in fish. They then inserted genes architects Hox fish in transgenic mouse embryos and saw that they were active only in the arms of the mice, but not in his fingers, showing that the DNA of fish does not have the elements Genetic essential to the formation of the fingers. Published in the journal PLoS Biology , these results highlight the fact that the digital part of the members of terrestrial animals is the result of a development from a pre-existing infrastructure ancestral DNA, although this represents an evolutionary novelty in tetrapods.

During embryonic development animal genes Hox or "architect genes" are responsible for the organization of the structures of the body. Fish and mammals have groups of genes Hoxa and Hoxd , both of which are necessary for the formation of fins and limbs. The team of Denis Duboule, a professor at the University of Geneva (University of Geneva) and the Ecole Polytechnique Fédérale de Lausanne (EPFL), has recently shown that during development of mammals, Hoxd genes depend on structure "bimodal" three-dimensional DNA to direct the development of members. This genetic structure provides a subdivision of the member in an arm and a hand. Fish them at the fins, do not show this subdivision. ancestral control strategy ... "To determine the genetic origin of this subdivision in arm and leg during evolution, we compared the genetic processes at work during the development of fins and limbs, in embryos of zebrafish and mouse, "says first author of the study, Joost Woltering, researcher at the Department of Genetics and Evolution, Faculty of Science the University of Geneva.

Scientists were surprised to find a three-dimensional bimodal architecture similar DNA in the region of Hoxd genes in fish. These results indicate that the regulatory mechanism used to train members of tetrapods is probably predates the divergence between fish and tetrapods. "We expected the contrary that it is precisely this bimodal DNA conformation that makes all the difference in the production of members, compared to the fins," says Joost Woltering. ... that just needs to be modernized fingers would they therefore homologous rays, these bony structures located at the end of the fish fins? To answer this question, geneticists have inserted into mouse embryos genomic regions that regulate gene expression Hox in fish fins. "Surprisingly, the regulatory regions of the fish triggered gene expression Hox mainly in the arm, not in the fingers, explains Duboule.

Overall, this suggests that, during the transition between fins and limbs, the appearance of our fingers resulting from the modernization of an existing control mechanism. " "What probably happened is comparable to a renewal process, as is done in engineering structures to equip machines with obsolete technologies. In this case, it is a DNA primitive architecture which has a new "technology" to make fingers and toes, "says Joost Woltering. The fin rays are not homologous fingers

The researchers conclude that although the fish have a tool kit gene regulation Hox to produce fingers, this potential is not used as it is in tetrapods. Therefore, they believe that the fin rays are not homologous fingers tetrapods, although they depend in part on a shared control strategy. Geneticists now intend to find out exactly what has changed between DNA elements in fish and tetrapods. "Now we know a lot of genetic switches in mice, which direct the expression of genes Hox fingers. It is important to find out exactly how these processes work today to understand what showed fingers and promoted the colonization of land, "says Denis Duboule. For if our first terrestrial ancestor fours came out of the sea there are some 350 million years, it is sufficient to observe a lungfish, our closest living relative among fish, crawling on all four fins pointed to imagine likely the first stages of evolution on land.

Sunday, January 19, 2014

Jan. 17, 2014 — A new species of toad was discovered hiding in the leaf litter of the Peruvian Yungas. The word is used widely by the locals to describe ecoregion of montane rainforests, and translates as "warm valley" in English. The new species Rhinella yunga was baptized after its habitat preference. The study was published in the open access journal ZooKeys.

Like many other toads of the family Bufonidae the new species Rhinella yunga has a cryptic body coloration resembling the decaying leaves in the forest floor ("dead-leaf pattern"), which is in combination with expanded cranial crests and bony protrusions cleverly securing perfect camouflage. The different colors and shapes within the same species group however make the traditional morphological methods of taxonomic research hard to use to identify the real species diversity within the family. Nevertheless, Rhinela yunga is distinct from all related species in absence of a tympanic membrane, a round membranous part of hearing organ being normally visible on both sides of a toad's head.

"It appears that large number of still unnamed cryptic species remains hidden under some nominal species of the Rhinella margaritifera species group," explains Dr Jiří Moravec, National Museum Prague, Czech Republic.

Among the other interesting characteristics of the true toads from the family Bufonidae are a typical warty, robust body and a pair of large poison parotoid glands on the back of their heads. The poison is excreted by the toads when stressed as a protective mechanism. Some toads, like the cane toad Rhinella marina, are more toxic than others. Male toads also possess a special organ, which after removing of testes becomes an active ovary and the toad, in effect, becomes female.

Saturday, January 18, 2014

The five families of sclecophoidians are the oldest group of extant snakes with an ancestor some place in the Jurassic. One family (Xenotyphlopidae) is monotypic and restricted to Madagascar, one family (Anomalepididae) is found only in the Neotropics, One is restricted to Southeast Asia and New Guinea (Gerrhopilidae), a fourth (Leptotyphlopidae)has the rather odd distribution of Africa, southwestern Asia, Socotra Island, the southwestern United States southward to Argentina; and they are present on many Caribbean islands. But, Typhlopidae is almost pan tropical and the largest family with 257 described species.

Scolecophidians are not just of interest for the evolutionary novelty of their specialized diet of social insects and associated adaptations. Because they are the most ancient (deeply-branching) group of living snakes their relationships can be used to track plate tectonics better than any other vertebrate group.

In a new paper published in Caribbean Herpetology, S. Blair Hedges, Angela Marion, Kelly Lipp, Julie Marin, and Nicolas Vidal provide a taxonomic framework for typhlopid snakes of the Caribbean as well as other regions of the planet.

Molecular data reveal large numbers of undescribed species, inferring that the true species diversity of these snakes is greatly underestimated.

The authors complied three separate molecular datasets expanding the worldwide scol­ecophidian dataset, called here dataset A; an Australian typhlopid dataset, dataset B and an expanded West Indian typhlopid dataset, dataset C. The authors use new morphological data and 489 new DNA sequences, and propose a new taxonomic framework for the family Typhlopidae. Of 257 named species of typhlopid snakes, 92 are now represented in molecular phylogenies along with 60 additional species yet to be described.

The Afrotyphlopinae subfamily is distributed almost exclusively in sub-Saharan Africa and contains three genera: Afrotyphlops,Letheobia, and Rhinotyphlops. The Asiatyphlopinae subfamily distributed in Asia, Australasia, and islands of the western and southern Paciﬁc, and includes ten genera: Acutotyphlops, Anilios, Asiatyphlops gen. nov., Cyclotyphlops, Grypotyphlops, Indotyphlops gen. nov., Malayotyphlops gen. nov., Ramphotyphlops, Sundatyphlops gen. nov., and Xerotyphlops gen. nov. The Madatyphlopinae subfamily occurs only in Madagascar and includes one genus: Madatyphlops gen. nov. The subfamily Typhlopinae occurs in the New World and includes four genera: Amerotyphlops gen. nov., Antillotyphlops gen. nov., Cubatyphlops gen. nov., and Typhlops.

The authors note that the most common theme encountered in studying the evolution of these snakes is their close association with geography. Their occurrence on islands never connected to continents demonstrates they are capable of dispersing (rafting) over deep water, and at the same time their relationships track plate tectonics better than any other vertebrate group. Species have unusually small distributions, and many species may be known from a single locality, and sympatric species sometimes have no distinguishing scale counts. Thus many unsubscribed species have been discovered using molecular data. All of this makes them an intriguing group to study, for understanding biogeography, ecology, behavior, and speciation. The entire article can be found on-line.

Friday, January 17, 2014

Madagascar has a unique phylogenetic representation of reptiles that includes the enigmatic Malagasy blind snake of the family Xenotyphlopidae established by Vidal et al., 2010. The family currently contains one genus Xenotyphlops with the two species X. grandidieri Mocquard, and X. mocquardi both are presumably endemic to the same area in northwest Madagascar.

Photo to the left. The three reptile species originally described by Mocquard (1905, 1906) which were re-discovered in syntopy at Baie de Sakalava in northern Madagascar after more than 100 years without records. Xenotyphlops grandidieri (pink), together with the two skink species Paracontias minimus (brown with longitudinal lines of dark spots) and P. rothschildi (beige with black flanks).

François Mocquard, a French herpetologist described a number of species from Madagascar at the turn of the 20th century, including the two limbless skinks Paracontias minimus and Paracontias rothschildi and the typhlopid snake Xenotyphlops grandidieri. None of the three species was rediscovered and their status remained enigmatic and their Malagasy origin was in doubt. The type specimens remained the only known specimens.

Within the worm-like snakes (Scolecophidia), Xenotyphlopidae is most closely related to the species-rich and almost globally distributed family Typhlopidae. Together with the Asian family Gerrhopilidae, these three families form the superfamily Typhlopoidea. They have a biogeographic pattern characterized by major vicariance events, such as the break-up of Gondwana and the separation of India and Madagascar, events that might have promoted the diversification of major lineages. A recent molecular phylogeny of the Scolecophidia suggested a Cretaceous split between the genus Xenotyphlops and its sister group, the family Typhlopidae.

Considering the almost cosmopolitan distribution and species richness of the family Typhlopidae, the blind snake fauna of Madagascar appears species-poor, consisting of the three genera Ramphotyphlops (one species), Typhlops (11 species) and Xenotyphlops (two species). And, since 1980, only three new species of Malagasy blind snakes have been described (Xenotyphlops mocquardi, Typhlops rajeryi and Typhlops andasibensis). Their discovery has been opportunistic rather than in the framework of a comprehensive revisionary work.With the exception of the probably introduced and parthenogenetic Ramphotyphlops braminus, all species of Malagasy blind snakes are endemic to the island and occur in a wide variety of habitats, ranging from xeric savanna at the coast to deciduous forest and rainforest Most of the species are known only from a few localities.

None of Mocquard the three species were rediscovered and their status remained enigmatic and even their Malagasy origin was considered questionable by somke authors. The type specimens remained the only representatives for more than a century, until Köhler and colleagues discovered all three of Mocquard’s taxa at the same locality within the same habitat confirming their Malagasy origin, in 2007-2008.

Prior to this Wallach & Ineich had noticed the morphological uniqueness of Typhlops grandidieri and placed it in the genus Xenotyphlops with X. mocquardi, based on differences in morphological and anatomical characters to X. grandidieri.

In general appearance, Xenotyphlops are purple to pinkish, thin, medium-sized blind snakes (SVL 163-276 mm), with a strongly pointed rostral scale and a complete lack of eyes. They are also unique in having a large, circular and nearly vertical rostral, and a single anal shield. Internally, it lacks a tracheal lung, has a type G foramen in the right bronchus, an anteriorly positioned heart and a large heart-liver gap.

In a new paper Wegener et al. (2013) used DNA from the 2007 specimens and found the two species of Xenotyphlops genetically similar and the morphological variability of X. grandidieri is thus greater than formerly thought. DNA sequences of the cytochrome b gene provide no indication of the occurrence of more than one species of Xenotyphlops in the Baie de Sakalava area despite the morphological variation found in specimens from this site. Due to the absence of clear diagnostic characters they consider X. mocquardi a junior synonym of X. grandidieri resulting in a monotypic genus Xenotyphlops and a monotypic family Xenotyphlopidae. This conclusion is supported by the distribution of both taxa, which are in close geographic proximity. To protect this unique relic species as well as other presumed endemics classified as Critically Endangered by the IUCN the authors suggest establishing a littoral (coastal) nature reserve along the coast east and southeast of Antsiranana.

Tuesday, January 14, 2014

The discovery of well-preserved pelves and a partial pelvic fin from Tiktaalik roseae, a 375 million-year-old transitional species between fish and the first legged animals, reveals that the evolution of hind legs actually began as enhanced hind fins. This challenges existing theory that large, mobile hind appendages were developed only after vertebrates transitioned to land. The fossils are described by scientists in the Proceedings of the National Academy of Sciences, online on Jan. 13.

This is an updated illustration of Tiktaalik roseae

in its natural
environment. Credit: University of

Chicago, Neil Shubin

"Previous theories, based on the best available data, propose that a shift occurred from 'front-wheel drive' locomotion in fish to more of a 'four-wheel drive' in tetrapods," said Neil Shubin, PhD, Robert R. Bensley Distinguished Service Professor of Anatomy at the University of Chicago and corresponding author of the study, which marks his inaugural article as a member of the National Academy of Sciences. "But it looks like this shift actually began to happen in fish, not in limbed animals."

Discovered in 2004 by Shubin and co-authors Edward Daeschler, PhD, Associate Curator of Vertebrate Zoology at the Academy of Natural Sciences of Drexel University, and the late Farish A. Jenkins, Jr., PhD, of Harvard University, Tiktaalik roseae represents the best-known transitional species between fish and land-dwelling tetrapods.

A lobe-finned fish with a broad flat head and sharp teeth, Tiktaalik looked like a cross between a fish and a crocodile, growing up to a length of 9 feet as it hunted in shallow freshwater environments. It had gills, scales and fins, but also had tetrapod-like features such as a mobile neck, robust ribcage and primitive lungs. In particular, its large forefins had shoulders, elbows and partial wrists, which allowed it to support itself on ground.

However, only specimen blocks containing the front portion of Tiktaalik have been described thus far. As the researchers investigated additional blocks recovered from their original and subsequent expeditions to the dig site in northern Canada, they discovered the rear portion of Tiktaalik, which contained the pelves as well as partial pelvic fin material. The fossils included the complete pelvis of the original 'type' specimen, making a direct comparison of the front and rear appendages of a single animal possible.

The scientists were immediately struck by the pelvis, which was comparable to those of some early tetrapods. The Tiktaalik pelvic girdle was nearly identical in size to its shoulder girdle, a tetrapod-like characteristic. It possessed a prominent ball and socket hip joint, which connected to a highly mobile femur that could extend beneath the body. Crests on the hip for muscle attachment indicated strength and advanced fin function. And although no femur bone was found, pelvic fin material, including long fin rays, indicated the hind fin was at least as long and as complex as its forefin.

"This is an amazing pelvis, particularly the hip socket, which is very different from anything that we knew of in the lineage leading up to limbed vertebrates," Daeschler said. "Tiktaalik was a combination of primitive and advanced features. Here, not only were the features distinct, but they suggest an advanced function. They appear to have used the fin in a way that's more suggestive of the way a limb gets used."

Tiktaalik pelves were still clearly fish-like, with primitive features such as an undivided skeletal configuration, as opposed to the three-part pelvic girdle of early tetrapods. However, the expanded size, mobility and robusticity of the pelvic girdle, hip joint and fin of Tiktaalik made a wide range of motor behaviors possible.

"It's reasonable to suppose with those big fin rays that Tiktaalik used its hind fins to swim like a paddle," Shubin said. "But it's possible it could walk with them as well. African lungfish living today have similarly large pelves, and we showed in 2011 that they walk underwater on the bottom." (For a video of a walking lungfish see:http://www.uchospitals.edu/news/2011/20111212-lungfish.html).

"Regardless of the gait Tiktaalik used, it's clear that the emphasis on hind appendages and pelvic-propelled locomotion is a trend that began in fish, and was later exaggerated during the origin of tetrapods," Shubin said.

Shubin will be hosting a three-part TV series based on his book "Your Inner Fish," on PBS in April 2014, tracing the origins of the human body through the DNA of living animals and the legacies of now-extinct, but biologically important species such as Tiktaalik roseae.

The study, titled "The Pelvic Girdle and Fin of Tiktaalik roseae," was funded by the National Geographic Society, Dane and Louise Miller, the Brinson Foundation, the Putnam Expeditionary Fund of the Museum of Comparative Zoology of Harvard University, an anonymous donor to the Academy of Natural Sciences, the University of Chicago and the National Science Foundation. Casts of Tiktaalik roseae are on permanent display at the Field Museum in Chicago, the Academy of Natural Sciences of Drexel University in Philadelphia and the Harvard Museum of Natural History in Boston.

Sunday, January 12, 2014

The following article is from the Star-Telegram and is a reminder that the extinction of rattlesnake round-ups is controversial. From the quotes contained here solving the rattlesnake round-up issue is clearly an educational issue. Texas schools should be including discussions on how local wildlife is best used. and it should be accompanied with public information campaign about the number of snake bites and the value of snakes and other wildlife.

Proposal to ban “gassing” of rattlesnakes in Texas ignites backlash in Sweetwater

State wildlife officials are circling Texas seeking public views on banning the controversial but 6-decade-old use of gasoline fumes to drive hated rattlesnakes out of cracks, crevices and sinkholes, and into the clutches of hunters who enter them at rattler roundup contests with top prizes of $500 or sell them to dealers at $10 a pound or more.

Nowhere is the proposed rule change as emotive a topic than in Sweetwater, 192 miles west of Fort Worth, a town of 10,600 that swells to 35,000 during the “world’s largest rattlesnake roundup” each March. A ban could cripple the festival, predict officials, who say 80 percent of the snakes brought in are caught by gassing.

Not only is it the annual event in Sweetwater, the roundup raises as much as $55,000 that local Jaycees recycle as donations to a hospice and the Fire Department. The funds also cover a dinner for the child advocacy center, Thanksgiving meals for more than 600 people, anonymous Christmas gifts to needy families and bicycles to eight students with perfect attendance, Jaycee David Sager said.

Unlike Fort Worth, where just three people spoke and all fervently in favor of a ban, the Texas Parks and Wildlife Department is expected to get a larger, far different reception in Sweetwater.

“Last time I heard, rattlesnakes were not an endangered species,” Sweetwater Mayor Greg Wortham thundered over the phone.

Like many in his town, Wortham sees gassing as the most effective way to catch a snake, whose bite can cause fatal swelling in calves and threaten the lives of humans.

“Suddenly there’s a problem,” he went on. “My father almost died from a rattlesnake bite. But to hear these people, we’ve got to save them. People in Austin don’t understand. We’ve got to protect our families, ranchers, people who work in oil fields, on wind turbine sites.”

The wholesale hunting, driven by big cash awards and payments, helps keep the snake population in check, the mayor insisted.

But as host of the roundup, Sweetwater has gotten a bumper crop of angry letters and online comments from out-of-state conservationists, mainly of the Yankee variety, for allegedly abusing the Western diamondback rattlesnake, he said.

“If they love them so much, I might just start a rattlesnake relocation program and send a FedEx box full of their favorite snakes to Massachusetts.”

So culturally ingrained is rattler hatred in parts of West Texas that nothing wildlife officials may say would convince Wortham and his constituents.

John Davis, the department’s wildlife diversity program director, said the proposed rule change resulted from a petition received in March 2013. “In responding to that, we felt that the data indicated it was time to propose a rule to address the threats this means of [catching] presents,” he said.

Citing a number of studies, Davis told the Fort Worth audience not only that gas fumes kill as many as half the snakes that don’t escape, but also that the tactic is indiscriminant.

Moreover, the vapors can kill a host of other animals and insects, some 26 on the federal endangered list, like the nearly blind spiderlike Colkendolpher Cave harvestman, not to mention fouling habitats for other species.

“We should not allow this anywhere in the country,” said herpetologist Kristen Wiley, curator of the Kentucky Reptile Zoo & Venom Sales of Slade, Ky., a nonprofit producer of venom for canine and equine snakebite vaccine.

Nor would she mind if the proposed ban strangles rattlesnake roundups.

Like the Humane Society of the United State, Wiley contends that the roundups abuse animals. “I’ve seen a roundup picture of a live snake with its mouth sewn shut,” she said, noting that snakes can be bagged with scores of others and, disoriented, dropped to the ground at a roundup from a height of 4 or 5 feet.

“They are raising money by torturing animals.”

Critics of gassing assert that rattlers can still be caught, and humanely, by going when the weather is right so the snakes can be plucked up as they sun themselves outside their dens.

Sager, 63, who has hunted snakes since childhood, says one would be lucky finding four or five snakes this way after walking miles, whereas pumping gas fumes would quickly net as many as 50.

Nonetheless, a Fort Worth snake fancier named Clint King photographed about a score of diamondbacks laying in a pile outside a crevice with more crawling out.

One of the people who can see both sides of the issue is Clark E. Adams, a professor of wildlife and fisheries sciences at Texas A&M University, and a co-author of a book on Texas roundups.

Hunters know that other species are affected by gassing, “because they see them running out” of the caves, Adams said in a telephone interview.

“But it’s not an issue to most of them,” he went on. “What it comes down to fundamentally is that you have to get rid of the snakes on your ranch. One female had 30 ovaries, meaning 30 more snakes. They have to be removed in one shape or form for the safety of humans.” And gassing, he said, “is still the most effective way to get them out of the den.”

Ken Darnell, a critic of the parks and wildlife proposed ban who is an Alabama patent attorney and snake venom buyer, maintains that the department already has hurt his industry by requiring permits and new reporting requirements, leading to the drop in hunters from 4,000 to about 800 in the past decade. The recent death of a major buyer in the South Texas town of Freer closed a sprawling operation where the snakes were largely caught in the open without gassing, he said.

While he personally opposes the use of gasoline fumes, Darnell asserted that a ban could lead to a critical shortage of antivenin for snakebite victims.

Davis dismissed the prediction in a Jan. 9 email, citing a statement from British-owned, Utah-based BTG-Protherics, the major antivenin manufacturer, which said it collects its venom in house. “BTG has all its own Crotaline (subfamily, including diamondbacks) specimens. Venom is produced under strict laboratory protocols and outside venom sources cannot be used.”

Well, not exactly.

Richard Straight, a former university scientist who is director of the Utah operation, clarified Friday that it has produced “most” of its own venom and became self-sufficient for Western diamondbacks only with the 2014 production. Straight said it will continue to buy Eastern diamondback venom from Biotoxins of St. Cloud., Fla., because the climate in the southeast is more suitable for the species than Utah.

Darnell disputes Straight’s assertions.

He said his venom, much of it collected in Texas, is pooled with that from Biotoxins and another Florida producer, then Biotoxins ships it to BGT and handles the marketing. If BGT is now self-sufficient, he asserted, it’s only because it stockpiled 5 kilograms of venom over the past two, three years.

“Straight will have to admit it under oath if this ever goes to court,” said the 69-year-old attorney-venom purveyor, who said last week that he had received a $202,000 check for three months of shipments.

Parasites are an important but often overlooked part of food webs and biodiversity. One estimate places 40% of the known species as parasitic. The number of amphibians species and amphibian parasites is about 1:1, for reptiles it is about 1 reptiles species for 2 parasites, and for birds it is about 3.5 parasites for each species. Of course the actual number of parasites species per species is probably much greater.

In a forthcoming article Kelehear and colleagues examine the diversity of pentastomids in Australian snakes. Pentasomids are endoparasites of the respiratory system of vertebrates, maturing primarily in carnivorous reptiles. Adult and larval pentastomids can cause severe pathology resulting in the death of their intermediate and definitive hosts. The study of pentastomids is a neglected field, impaired by risk of zoonoses, difficulties in species identification, and life cycle complexities.

Pentastomids are long-lived endoparasites of the respiratory system of vertebrates, and are arguably the oldest metazoan parasites known to science. Prehistoric larvae resembling extant primary larvae appeared in the fossil record approximately 100 million years prior to the vertebrates they now parasitize. Larval pentastomids enter their definitive host when it consumes an infected intermediate host. These larvae tunnel out of the digestive system and through their definitive host to the lungs, generating lesions and scars along their migration path. In intermediate or accidental hosts these larvae can establish widespread visceral infections. In humans, pentastomiasis may be transmitted via food or water contaminated with their eggs, or via consumption of undercooked snake flesh. Adult pentastomids feed primarily on blood from host capillary beds in the lungs and can cause severe pathology resulting in death. Adult pentastomids reach large body sizes (up to 15 cm), physically occluding respiratory passages and inducing suffocation. The two pairs of hooks they use for attaching to lung tissue can cause perforations and haemorrhaging, and degrading molted cuticles shed into the lung lumen by growing pentastomids may induce putrid pneumonia.

Kelehear et al. surveyed wild snakes in tropical Australia to determine which host species possess these parasites, and then attempted to identify the pentastomids using a combination of morphological and molecular techniques. Pentastomid infections occurred 59% of the 81 snakes surveyed. They ubiquity of pentastomid infections in the snakes sampled alarmingly high considering the often-adverse consequences of infection and the recognized zoonotic potential of these parasites. The pentastomids identified were in the genera Raillietiella and Waddycephalus and infected a range of host taxa, encompassing seven snake species from three snake families. All seven snake species represent new host records for pentastomids of the genera Raillietiella and/or Waddycephalus. The arboreal colubrid Dendrelaphis punctulatus and the terrestrial elapid Demansia vestigiata had particularly high infection prevalences (79% and 100% infected, respectively). Raillietiella orientalis infected 38% of the snakes surveyed, especially frog-eating species, implying a frog intermediate host for this parasite. R. orientalis was previously known only from Asian snakes and has invaded Australia via an unknown pathway. Their molecular data indicated that five species of Waddycephalus infect 28% of snakes in the surveyed area. And their morphological data indicate that features of pentastomid anatomy previously utilized to identify species of the genus Waddycephalus are unreliable for distinguishing species, highlighting the need for additional taxonomic work on this genus. This open -access article is on-line in early view.

Thursday, January 9, 2014

by Sathya Achia Abraham
Experts predict that 2014 will be a big year for reptiles. Reptiles, which include snakes, lizards, turtles, crocodiles, tuataras and amphisbaenians, are projected to become the most diverse vertebrate group in the world. As it stands now, there are approximately 10,000 bird species – the most of any vertebrates – but reptiles are forecast to reach and surpass that milestone in 2014.

Among the experts studying these developments is Peter Uetz, Ph.D., associate professor of systems biology and bioinformatics in the Center for the Study of Biological Complexity (CSBC), part of Life Sciences at Virginia Commonwealth University. Uetz is the founder, editor and curator of the Reptile Database, a web-based catalogue of all living reptile species and classification. The catalogue is shared with several global projects that collect similar information for other living species on the planet.

In 1995, as a graduate student at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, Uetz founded the Reptile Database while working on his thesis project, which focused on vertebrate limb development. His interest in web technologies was initially sparked by the EMBL DNA sequence database and the new opportunities the worldwide web offered in the early 1990s.

The Reptile Database has become a collaboration of hundreds of scientists and hobbyists around the world who study reptiles. Currently, the database includes 9,900 species of reptiles, including another 2,800 subspecies.

According to Uetz, the Catalogue of Life (CoL), a consortium of 133 species databases, uses the taxonomic information from the Reptile Database and passes its information to the Encyclopedia of Life. The Encyclopedia of Life, said Uetz, is an ambitious project that plans to set up a web page for each of the roughly 2 million species on the planet.

Why study reptiles?
For many, a slithering, scaly snake offers a hefty dose of fear, panic and dread, but it may also help scientists advance the treatment of human disease.

While the legless reptile is critical in conservation of the natural environment and controlling pest populations – and thus keeping their ecosystems in check – they also play a key role in research, serving as model organisms of study.

"From a research perspective, reptiles have a couple of unique and amazing features that make them very interesting to study and learn about," Uetz said.

An example is in the genetics of sex and reproduction. According to Uetz, many reptiles have temperature-dependent sex determination, which means that the sex of their offspring does not depend on X and Y chromosomes the way it does in most mammals. Rather, sex determination in many reptiles is dependent on environmental temperature.

"There are also dozens of species that are parthenogenetic – there are no males but only females," Uetz said. "The genetic basis of these phenomena is poorly understood, but most likely of general importance as there are many other species which have such features."

Scientists hope to advance the treatment of human diseases based on what they are learning from studies of snake development, metabolism and protein structures and function. For example, understanding the molecular makeup of toxic snake venom could lead to the development of therapeutic drugs to help save human lives. Examining snake genes and proteins may allow researchers to gain important clues into the functioning of molecular pathways in humans and other vertebrates.

"In fact, the saliva of the poisonous Gila monster, a lizard found in the southwestern U.S. and Mexico, has already yielded the drug exenatide for the management of type 2 diabetes," Uetz said. Exenatide is marketed as Byetta and is administered as an injection under the skin. The drug stimulates the pancreas to secrete insulin when blood sugar levels are high, according to the National Institutes of Health.

"Given that there are hundreds of other compounds in snake and lizard toxins, many more drugs can be expected from reptiles," he said.

Lastly, by mapping the snake genome, evolutionary biologists can learn more about the evolution from lizard to snake. Knowledge gained here could provide critical insight into limb development and one day help researchers understand the same processes in humans. This arena is of particular interest to Uetz, given his previous research at the European Molecular Biology Laboratory in vertebrate limb development. According to Uetz, snakes evolved from lizards by losing their limbs, with rudimentary limb bones left in some species.
Recent findings: snake genome

A study published online in the December 2013 issue of the Proceedings of the National Academy of Sciences, led by Todd A. Castoe, Ph.D., assistant professor of biology at the University of Texas at Arlington, detailed the findings of the first complete snake genome of a Burmese python – a huge, non-venomous snake with a giant appetite. According to Uetz, who contributed peripherally to the study via the Reptile Database, the team showed that hundreds of genes are switched on in response to a meal.

"We don't know the meaning of many of these genes and how they help the snake digest and process all that food, but one thing that happens is that snakes have dramatic proliferation of intestinal cells that help with digestion," Uetz said.

"And it's not only the genes in the intestine, it's also liver genes and all kinds of other things that happen in the snake body as a response to feeding. This is an interesting physiological adaptation that may help to understand how obesity works."

Uetz is working on a detailed follow-up study addressing certain questions of evolutionary biology, including how some of the genes may play a role in limb development.

"Related to our snake genome project is our work to understand how genes affect limb development – or the disappearance of limbs," Uetz said. "Limbs have been lost dozens of times in evolution. There are many lizards which have lost their limbs independently."

"The first snake genomes will help us to find the mutations that happened in the past when limbs were reduced and eventually lost. This will also help us to understand limb development in general, which down the road may be applied to understanding how humans develop limbs."

Moving forward, Uetz hopes scientists will gain a detailed phylogenetic tree of reptiles through collaborations made possible by the Reptile Database. In 2013, Uetz said, the scientific community produced publications highlighting genome sequencing for two turtles, a crocodile and two snakes. He said a lizard genome was the first reptile genome when it was published two years ago.

"The phylogenetic tree of reptiles and most other vertebrates has been studied intensively during the past decade," Uetz said.

"The next 10 or 20 years will be focused on how genes determine the morphological and physiological traits of these species—that is, the evolutionary adaptations that separate them from amphibians or birds (which are essentially reptiles) and mammals."

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